LAUSR

Abstract Simulations of the dynamic behavior of a sonar cable array towed by an underwater vehicle considering the influence of flow field disturbed by the underwater vehicle and its propeller are challenging tasks. In present paper, the strongly nonlinear towed sonar cable array is modeled by the Lumped-Mass method where the cable array is discretized into a series of massless springs and lumped-mass points. The drag force on the towed sonar cable array is obtained by calculating the drag force on each lumped-mass point considering the flow field of the underwater vehicle and its propeller, which is computed by CFD methods. The dynamic behavior of the towed sonar cable array is simulated by 4th Runge–Kutta method applying Newton's second law. Simulations of the three underwater vehicle motion modes including linear motions, turning motions and surfacing motions are performed. The results show that the numerical method proposed is reasonable, and the lateral deflection of the towed sonar cable array is related to the speeds and the motion modes of the underwater vehicle.